Cerebral autoregulation is preserved in multiple sclerosis patients

Abstract

Multiple sclerosis (MS) is an inflammatory disease that may also be associated with vascular dysfunction. One master component of vascular regulation is cerebral autoregulation (CA). We aimed to investigate the integrity of CA in MS patients and study its relationship with autonomic dysfunction (AD), magnetic-resonance-imaging (MRI) lesion load and hemodynamic parameters. We enrolled 20 relapsing-remitting MS and 20 healthy subjects. CA was assessed by transfer function analysis parameters (coherence, gain and phase), as obtained in the very low, low and high-frequency domains (VLF, LF, HF, respectively). We evaluated the autonomic parameters heart rate variability and spontaneous baroreflex sensitivity (BRS). There were no significant differences in CA parameters between MS and controls (p>0.05). Lesion load was not correlated with any CA parameter. LF gain was positively correlated with BRS in both groups (MS: p=0.017; controls: p=0.025). Brainstem lesion load in MS was associated with higher systolic blood pressure (SBP; p=0.009). Our findings suggest that CA is preserved in our MS cohort. On the other hand, AD in MS patients with brainstem lesions could contribute to the increase of supine SBP. Whether this systemic deregulation could contribute to disease burden remains to be investigated.

Keywords: Autonomic nervous system; Cerebral autoregulation; Heart rate variability; Magnetic resonance imaging; Multiple sclerosis; Spontaneous baroreflex sensitivity.